[herokusaki]

> there are many server plugins you can install to prevent griefing or building.

I think what would suit their use is a plugin that rather than prevent building would make the world slowly regenerate towards a preset form (the map of Denmark).

Edit: Either that or create an incentive for players to restore and maintain key landmarks with premium items. ("Rebuild Copenhagen and get diamond armor! Help defend it for X redstone per day!" or something like that. What do successful freemium Minecraft servers offer their sponsors?) These sorts of quests will probably help keep the players interested for longer and produce viral stories as well, so more people will visit virtual Denmark.